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Content tagged 'rotax 912 overspeed'

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  1. Hey Guys...a sad week end just passed. You probably already know that I was struggling with my previous GSC/warp drive prop. Indeed when I applied full power for t/off I usually set the pitch at about 5300 (that's before the plane is moving) and this way I got 5700rpm at climb out, later to be set at about 5500. Unfortunately my prop was feeding back too much force into / through the linkage and bending a bracket doing so. The result was that just when taking off, the prop went into a finer pitch and made the engine go beyond 5800Rpm. At first I did not realize what was happening as at each take off I had to dial in a bit more/coarser pitch....Once I had a real bad overspeed going well beyond what Rotax accepts. Of course I reduced power as quick as i could and as I was already flying I kept going and landed safely at my home lake. When I read out my Rpm gauge History my heart sunk....7400Rpm
    Now officially this means the engine is toast even if it only lasted a couple of seconds. As I fly over lakes all the time, mostly alone I took the decision at first to do the overspeed inspection (compression, filter, borescoped the cylinders etc) and see if the engine keeps me going. There was no sign of anything wrong for about 7 Hrs (besides a little voice in my head) but on my last two flights....not so good. The engine was much harder to start and was running a bit rough (these are some signs of overspeed damage)
    To cut the story short, I have removed my engine (912 UL) and I will replace it wit a overhauled 912 ULS. Here the reasons....some obvious 
    1.Engine experienced overspeed
    2.Don't know if previous owner has had issues / overs speeds (probably yes)
    3.Engine was fitted with the Xtra kit boosting compression ratio....Rotax issued a service bulletin totally against that mod (maybe too much pressure on the 2 piece crank?)
    4.I fly in very remote areas and if I have an engine out it will be VERY costy to get the aircraft back home.
    5.I might damage the Cat doing an engine out landing....costing in the end more than an overhauled engine
    6.Overhauled engine will have all SB. and mods done (by rotax distributor ROTECH)
    7. Last and not least ...get rid of that little voice in my it right
    Here some pictures of my ordeal....actually the Cat looks real good without engine....